Solution filtration method for polycarbonate purification
First Claim
Patent Images
1. A method for purifying polycarbonate, which method comprises passing a solution comprising polycarbonate and methylene chloride through a filtration system having filters, wherein the filtration system reduces the level of particulates having a size greater than 0.5 microns to below 10,000 per gram of the solution, and the filtration system is continuously operated for a period of greater than 15 days without switching or cleaning a filter.
1 Assignment
0 Petitions
Accused Products
Abstract
The specification provides a description of a superior method of making polycarbonate containing fewer particulates by using a specific filter system for filtering organic solvent solution of polycarbonate resulting from phase separator of aqueous-organic mixture from reactor.
11 Citations
7 Claims
- 1. A method for purifying polycarbonate, which method comprises passing a solution comprising polycarbonate and methylene chloride through a filtration system having filters, wherein the filtration system reduces the level of particulates having a size greater than 0.5 microns to below 10,000 per gram of the solution, and the filtration system is continuously operated for a period of greater than 15 days without switching or cleaning a filter.
Specification